Where Do Young Earth Creationist Get The "6000 Year Old Earth" From?

I'm sure you would not find it surprising that the person has zero scientific background.

Considering the fact that it was the cult of the Seventh-Day Adventist church that I escaped from; I was quite surprised to find out the "6000 year old earth" premise was the brain-child of SDA church founder, Ellen White.

Its also rather amazing to realize that for about 60 years after Darwin published Origin, creationism was not mainstream. It was most likely in relative decline, then resurged in the 1920s.

Ron Numbers gave a brief history of creationism, reminding us that perhaps a majority of the people in the world reject Darwin, and he also emphasized a few facts in that history that many would find surprising.

There was no organized opposition to evolution until the 1920s, when it was marshalled by William Jennings Bryan, who was most concerned about the ethical implications of evolution. He made the point that the popular movie about the Scopes trial, Inherit the Wind, was historically inaccurate. One of the most memorable moments in the movie was when Darrow pinned Bryan down on the date of the creation to 4004 BC…but Bryan had no such preconception. The primary strain of creationism at that time had absolutely no problem with the age of the Earth, and Bryan plainly stated in interviews and speeches that he was a proponent of the day-age theory, in which the "days" of creation week were not required to be 24-hour modern days.

These early creationists had no bone to pick with geology at all, and were unperturbed at the thought that the world was hundreds of millions of years old. The two dominant explanations were the day-age theory, which stretched out the time-span of creation week to cover the whole of geological time, and gap theory, which argued that between the creation of the world mentioned at the beginning of Genesis, and the account of the 6 creation days, there was a long undocumented period of time in which geological history occurred. The latter model was also popular because it was presented in the Scofield Reference Bible, which specifically placed the geological column in a 'gap' in the account, and stated that the 6 days referred to the creation of Eden.

The dissenters from this position were a tiny minority, the Seventh Day Adventists, who were regarded as weird by the majority of fundamentalists. The Seventh Day Adventists credited a source of divine information other than the Bible, the prophecies and visions of their founder, Ellen White, who was the source of the idea that Genesis had to be describing a literal six 24-hour day creation occurring 6000 years ago. Her disciple, George MacReady Price, came up with the idea of wedging all of geology into the Noachian Flood. These were not popular ideas.

The mainstreaming of literalist creationism occurred in the 1960s, when John Whitcomb and Henry Morris wrote The Genesis Flood. It's basically the same nonsense he Seventh Day Adventists were peddling, but Whitcomb and Morris were not SDAs, making it possible for conservative Christians, who regarded Seventh Day Adventism as a freaky cult, to coalesce in the formation of the Creation Research Society. These people had no ambition to convert the research community, but instead wanted to wean bible-believers away from what they considered the compromises of day-age and gap theory.

Another consequence of this shift was that it opened up hard-core creationists to a kind of hyper-evolution: they had to explain how a small ark of fixed size could contain all the animals in the world, so they had to postulate a small number of created "kinds" that diversified into new species after the flood, at a pace evolutionary biologists consider absurd.

In the early 1980s, these new, literal creationists got ambitious and started trying to push into classrooms by legislation, efforts that got stymied by major court decisions in Arkansas and Louisiana, which ruled that mandatory teaching of creationism was unconstitutional. One consequence of the Arkansas decision was that, when the creationists had been anticipating victory, they had begun assembling a creationist textbook. When they lost instead, they had to rewrite to remove the word "creationism" and replace it with "intelligent design".

Numbers talked a bit about Intelligent Design, and argued that it was different from the previous version of creationism…but not in a good way, or in a milder way. The brainchild of Philip Johnson, Intelligent Design was far more radical than the previous iterations — Johnson opposed methodological materialism, and specifically wants to incorporate god into science. While arguing that ID is something new, though, he also made it clear that it is not because ID is a secular theory — it's an extraordinarily religious idea, backed by religious proponents, and funded by theocratic extremists like Howard Ahmanson.

He ended by giving us the discouraging news that 65.5% of Americans believe in creationism, and that the movement is expanding beyond US borders to the Islamic and Jewish world, too. Bummer, man. He could have at least offered some hope for the future.

I had thought that perhaps creationists had counted back through the series of lineages given in the Old Testament to arrive at the number.

I believe that this is how they got the number, more-or-less. Its still a loony idea though, and makes the assumption that the bible is 100% linear, and covers 100% of time.

As for the appeal, PZ mentions that the opposition to evolution started by people concerned of the "ethical implications of evolution" - probably stemming from the fact that evolution makes some of the bible wrong.

Prohibition was more of a Methodist thing. Adventists prescribe to a strict no meat and no alcohol diet, so probably weren't concerned with their members drinking as much. Although I can't speak with certainty for that time, I know my experience with Adventists is that they tend to have a self contained 'bubble community' - and avoid non-Adventists whenever they can. In the more extreme sects, they find a huge piece of land and 'pioneer' it, setting up a self sustaining community; a compound of sorts. Branch Davidians are one of the most extreme schisms of Adventism (for those that don't recall, David Koresh of Waco fame was a Branch Davidian).